M1 - M2 - M3 euler fine tuning geometriy parameters, posted by Antje Trapp on 19 May 2024, 14:49 
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We fine tuned geometry parameters for linear effects on X motion (parallel offset) for all three mirrors.
dTz was corrected for M2 and M3 to -6.5mm (same geometry)
dTz was corrected for M1 to +6mm |
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Issue, posted by Jan Gruenert on 28 Jan 2024, 13:50
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RC / BKR informs : Beam is down (since 12h10), all beamlines affected
The reason is failure of a quadrupole (power supply) downstream of the dogleg.
The MPS crew is working on recovery, access to XTL ongoing. |
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Issue, posted by Romain Letrun on 01 Feb 2024, 21:56
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At 21:29:20 today, the number of bunches in SASE1 was increased from 1 to 352 without intervention of the SPB/SFX shift crew. 30 seconds later, the number
of bunches was reduced to 1, again without intervention from the SPB/SFX shift crew (see attachments 1 and 2).
We were in the middle of a measurement at that time and the sudden increase from 10 mW to 3.5 W average power resulted in the destruction of |
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Issue, posted by Romain Letrun on 13 Feb 2024, 08:52
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| Like after the previous winter maintenance period, the shutter of FXE appears as opened in DOOCS panels even though it is closed (https://in.xfel.eu/elog/OPERATION-2023/58). |
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Issue, posted by Tommaso Mazza on 17 Feb 2024, 08:15
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The cross on the FEL imager, which we use as a reference for BKR crew, is not centred on the GATT aperture. when was this changed, and why?
att. 1 and 2 show the current position (the saturated image aids the positioning of the GATT aperture).
att. 3 is from two weeks ago. then, the cross was centred on the GATT aperture. |
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Issue, posted by Romain Letrun on 27 Feb 2024, 09:56 8x
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The status of the XTD2 attenuators has been checked during the experiment last week and many were found to cause disturbances in the wavefront ranging
from mild to severe.
Attachment 1: No attenuator |
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Issue, posted by Peter Zalden on 28 Feb 2024, 06:57
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Not sure if this is the cause of the fringes reported before, but at 5.6 keV there are clear cracks visible on the XTD2 Attenuators 75 umm and 150um
CVD, see attached. There is also a little bit of damage on the 600 um CVD, but not as strong as the others.
At 5.6 keV we will need to use the thin attenuators. I will mention again in case this causes problems downstream. |
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Issue, posted by Romain Letrun on 04 Mar 2024, 09:42
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The number of bunches during the last night shift kept being changed down to 24 by the device SA1_XTD2_WATCHDOG/MDL/ATT1_MONITOR020 acting on SA1_XTD2_BUNCHPATTERN/MDL/CONFIGURATOR.
This was not the case during the previous shifts, even though the pulse energy was comparable. Looking at the history of SA1_XTD2_WATCHDOG/MDL/ATT1_MONITOR020,
it looks like this device was started at 16:26:25 on Friday, 1st March. |
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Issue, posted by Harald Sinn on 15 Mar 2024, 00:07
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SASE1 bunch number was reduced to 10 pulses for no obvious reason.
Traced it back to a malfunctioning of the watchdog for the solid attenuator (see attached error message)
Deacttivated the watchdog for SASE1 solid attenuator. Re-activated it again. |
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Issue, posted by Romain Letrun on 15 Mar 2024, 07:08
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There are now two watchdogs for the XTD2 attenuator running at the same time
SA1_XTD2_WATCHDOG/MDL/ATT1_MONITOR020
SA1_XTD2_OPTICS_PROTECTION/MDL/ATT1
that are configured differently,
which results in different pulse limits (see attachment). |
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Issue, posted by Harald Sinn on 16 Mar 2024, 12:12
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11:15 SASE1/SPB called that they observed and issue with the SASE1 XGM/XTD2: about every 35 seconds the power reading jumps from 4 Watts to zero and
back. It seems to be related to some automated re-scaling of the Keithlyes, which coincides. The fast signal and downstream XGMs do not show this behavior.
The concern is that this may affect the the data collection later today. |
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Issue, posted by Frederik Wolff-Fabris on 20 Mar 2024, 12:41
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BKR called PRC around 06:10AM to inform on vacuum issues at SA1 beamline leading to a lost beam permission for the North Branch.
VAC-OCD found an ion pump in the PBLM / XTD9 XGM presented a spike in pressure that triggered valves in the section to close.
After reopening valves the beam permission was restored; further investigations and monitoring in coming days will continue. Currently all systems |
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Issue, posted by Chan Kim on 28 Mar 2024, 14:56
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| Pulse energy fluctuation observed after full train operation in SA2 starts. |
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Issue, posted by Romain Letrun on 30 Mar 2024, 06:59
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DOOCS panels are again incorrectly reporting the FXE shutter as opened when it is in fact closed. This had been fixed after it was last reported in February
(elog:24), but reappeared now. |
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Issue, posted by Chan Kim on 30 Mar 2024, 22:02
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Continuous pointing drift in horizontal direction.
It may trigger a vacuum spike at SPB OH (MKB_PSLIT section) at 21:07 pm.
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Issue, posted by Andreas Galler on 01 May 2024, 16:39
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840 pulses not possible at SXP due to big brother settings for the EPS Power Limit rule. The minimum pulse energy was assumed to be 6 mJ while the actual
pulse XGM reading is 550 uJ.
Solution: The minimum assuemd pulse energy had been lowered from 6 mJ to 2 mJ. This shall be reverted on Tuesday next week. |
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Issue, posted by Raśl Villanueva-Guerrero on 08 May 2024, 13:51
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Dear all,
Due to a probable issue at the SA1 Transmissive imager, the "OUT" and "YAG" position indication signals seems to be not responsive.
After the FXE team noticed that MODE S was interlocked, the root cause has been narrowed down to this component. Later, further investigation |
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Issue, posted by Rebecca Boll on 10 May 2024, 00:04
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our pp laser experienced timing jumps by 18 ns today. this happened for the first time at ~7:30 in the morning without us noticing and a couple of more
times during the morning. we realized it at 15:30 due to the fact that the signal on our pulse arrival monitor (X-ray/laser cross correlator downstream
of the experiment) disappeared. we spent some time to investigate it, until we also see this jump in two different photodiodes different triggers (oscilloscope |
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Issue, posted by Andreas Koch on 14 May 2024, 09:56
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EPS issue for Transmissive imager SA1 (OTRC.2615.T9) w.r.t Operation eLog #96
The motor screen positions w.r.t. the EPS switches had been realigned (last Wednesday 8th May), tested today (14th May) and the EPS is again
enabled for the different beam modes. All is back to normal. |
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Issue, posted by Rebecca Boll on 25 May 2024, 02:38
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Today in the afternoon, SASE1 was tuned (a description of the activities in att 4). We now realize that this has in some form changed the SQS pulse parameters.
att 1 shows ion spectra recorded under nominally the same photon parameters before (run 177) and after (run 247)
it's also visible in the history of the SASE viewer that the behavior of the SASE3 pulse energy is different before and after 15:45, which |